number24 (Original Japanese Version) Season 1 Episode 9 Carbonic acid hot springs aren't too hot, so you can stay in them a long time.

Now that Seiichirou's problem has been resolved, the crew in Oita get to some serious relaxing. However, their team members back home are also dealing with various problems and anxieties. As Natsusa leaves Oita, Ibuki's mother suddenly appears.